Rust bluing

Regarding the model 54 winchester I asked about in the whats it worth area. I'm now thinking about restoring/returning the gun to a nice condition, new stock, re-blued, etc. I tried a cold rust bluing once upon a time several years ago on an old winchester .25-20 lever action gun (manufactured sometime around WW I, IIRC it had a nickle steel barrel) the receiver, trigger, lever, etc worked beautifully, The barrel pretty much just laughed at me. I think I sent it through the process 7 or 8 times and it took no color whatsoever. I threw in the towel and had it hot blued. Is there a secret to rust bluing the nickle steel?

Rust bluing is not a completely 'cold' process. The solution is applied to the metal and left to rust. Then, the metal is immersed in boiling water until it converts to black oxide, then it is carded off.

"Rust bluing is not a completely 'cold' process. The solution is applied to the metal and left to rust. Then, the metal is immersed in boiling water until it converts to black oxide, then it is carded off." Thats pretty much what I did- rather than full immersion, I poured boiling water over the parts and pieces. The barrel never formed even a hint of a black oxide, though the reciever, lever, hammer, trigger, etc did. I don't recall the exact formulae I used- I just remember using concentrated nitric acid with pure iron filings dissolved in the acid. I recall trying to be very carefull about degreasing- but I didn't use a lye bath or anything- just readily available degreasers- I think I used a buffing compound on the metal as well as wet or dry sand paper.

"A very labor intensive process, but correct for the Model 54."
Thats why I'm looking at the process again. I like to keep things "right" whenever posible.

We use commercial rust blue preparations like Pilkingtons, and have blued several pre-war Model 70 and Model 54 rifles with no difficulty.

1) Gun must be fully disassembled.
2) Polishing and metal prep must be perfect - rust blue hides nothing. We use a variety of drawfiles, and then buffing wheels through 600 grit. Note the difference in finish texture between the receiver and the barrel on this model.
3) The metal must be absolutely and thoroughly degreased. This is most likely where your problem lies. ANY oil, detergent, etc on the metal will either cause the blue not to take or cause spotting. We immerse the parts in 190-deg Dicroclean 909 (Brownells), then go to a cold bath in clean water.
4) On the first pass with the rust solution, it is critical to make it as smooth as possible without runs or overlaps.
5) The other likely problem is your water quality. Chemicals in your water will prevent the black oxide from forming. Use PURE water (reverse osmosis) in your boiling tank.
6) It may take several additional coats to get the rust blue to take on the nickel steel.

Remember that the fresh black oxide is very fragile. Handle the piece by the bore plugs and very lightly card the velvet off.

Great advice, but still may not work properly. Refer to Dunlap's book "Gunsmithing" for the formula for a pre-blueing etch for the barrel.
I have blued many nickel steel guns using Dunlap's Old American blue formula without a pre-etch, but note that ambient humidity is critical. We are on the water here and humidity is always at least 50 percent.
Plan on 10 passes. And, imerse your parts in boiling water rather than just pouring it over the parts. It comes out best if you boil for 20 minutes between passes. Brownells have blueing tanks and you can use a Coleman gasolene stove with one to accomplish your blueing. It worked for me for years.
If you imbed abrasive in the surface by using crocus cloth or some other polishing compounds, the part will not blue evenly. If your city water is like ours, they kill algae by dragging bags of copper sulphate through the reservoirs and the part will not blue evenly. Best you use distilled water and wear clean white cotton gloves.
You need to maintain a sterile atmosphere; you are undertaking one of the most difficult kinds of blueing and have to avoid contamination. Scoop every trace of oil from the water surface, should it boil out during heating. Make sure your carding brushes are sterile by boiling them in soda water.